Since the last update in Leap 42.3 to KDE 5.8.7, it lost the ability to run
user apps directly.

Scenario...

Won't work:
myapp.desktop points exec=myapp
Resulting in:
KDEInit could not launch 'myapp':
Could not open library 'libkdeinit5_myapp'.
Cannot load library libkdeinit5_myapp:
(libkdeinit5_myapp: cannot open shared object file: No
such file or directory)

Will work:
myapp.desktop points exec=/home/user/bin/myapp

Workaround:
Added export PATH="${PATH}:$HOME/bin" to ~/.bash_profile